Ischemic rectal necrosis after aortic valve replacement surgery successfully treated with conservative management

An 80-year-old female with history of aortic stenosis, heart failure, atrial fibrillation, hypertension and dyslipidemia underwent aortic valve replacement surgery. At 4th postoperative day (POD), she developed hemodynamic instability, followed by abdominal pain and bloody diarrhea. Abdominal computed tomography (CT) revealed wall thickening from descending colon to rectum and peri-rectal fat stranding (Figure 1). Sigmoidoscopy demonstrated diffuse dark purple discoloration of rectal mucosa with interspersed areas of ulceration (Figure 2) that extended to sigmoid, consistent with gangrenous ischemic proctosigmoiditis. Considering the importance of postoperative anticoagulation after placement of the mechanical aortic valve, emergency surgery was avoided. Vasopressor support, broad-spectrum intravenous antibiotics and bowel rest were started. She was closely monitored and, fortunately, evolved favorably with clinical and hemodynamical improvement. At 24th POD, there was symptomatic recurrence and sigmoidoscopy revealed friable granular rectal mucosa with no signs of active ischemia (Figure 2B). CMV was isolated in biopsies and valganciclovir was started with good response. At 65th POD, sigmoidoscopy revealed healing mucosa with areas covered by white exudate (Figure 2C). Biopsies were still weakly positive for CMV. Considering clinical and endoscopic improvement, it was interpreted as residual changes during the course of disease resolution. At 83rd POD, she was discharged home.

Keywords: ischemic colitis, ischemic proctosigmoiditis, rectal necrosis, gangrene.